Chess and Checkers: The Way to Mastership by Edward Lasker
Castling is permitted only when neither King nor Rook concerned has previously moved, when none of the squares between the King and the Rook are obstructed and when none of the three squares involved in the King's move are controlled by an adverse man. Thus if in check (see page 17) the player may not castle. In Diagram 4, neither White nor Black may castle.
+---------------------------------------+
8 | #R | #Kt| | | #K | | | #R |
|---------------------------------------|
7 | #P | #P | | | | #P | #P | #P |
|---------------------------------------|
6 | | | #P | | | | | |
|---------------------------------------|
5 | | | | #P | ^P | | | |
|---------------------------------------|
4 | | ^B | | | | ^P | | |
|---------------------------------------|
3 | | | | | #Kt| ^Kt| | |
|---------------------------------------|
2 | ^P | ^P | ^P | | | | ^P | ^P |
|---------------------------------------|
1 | ^R | | | | ^K | | | ^R |
+---------------------------------------+
a b c d e f g h
Diagram 4.
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Choose from the standard game or two variants: Fischer Random Chess and Red Square Chess.
